In-situ hydrothermal synthesis of Ag₃PO₄/g-C₃N₄ composite and their photocatalytic decomposition of NOx

Ag₃PO₄ and Ag₃PO₄/g-C₃N₄ were successfully synthesized by an in-situ solvothermal method using graphitic carbon nitride obtained by sectional heating of guanidine carbonate and AgNO₃ as starting materials. The composites were characterized by XRD, SEM, PL, DRS and BET. The photocatalytic performance was determined by deNOx reaction under different light wavelength irradiation. Ag₃PO₄/g-C₃N₄ composites with different ratio showed different band gap and morphology, and also decreased the photo-corrosion and self-corrosion by forming heterojunction. The photocatalytic deNOx ability of Ag₃PO₄/20%g-C₃N₄ was 15.52% under irradiation of visible light (>400 nm) and could be enhanced to 41.76% under irradiation of 290 nm. With the increment of the g-C₃N₄ content, high efficiency of charge separation induced by the formation of heterojunction between Ag₃PO₄ and g-C₃N₄.